Jump in Business Spending Seen as Key to Potential Breakout

The U.S. economy looks set to steadily accelerate after a weather-pummeled first-half crawl, but the most upbeat economists in The Wall Street Journal's monthly forecasting survey say the business sector holds the key to even stronger growth during the second half.

According to this month's survey of 43 economists—not all of whom answered every question—real gross domestic product is pegged to grow at an annual rate just shy of 3% in the third and fourth quarters. That would put GDP growth over the full year 2014 at 2%,...